Comparative study on ovsynch versus doublesynch protocol for estrus synchronization during summer and winter season in buffalo
Abstract
The present study designed for comparative evaluation of Ovsynch and Doublesynch estrus
synchronization protocol, mineral profile and oxidative stress in cyclic Murrah buffaloes (n=83) in summer and
winter season at farm and field level. The first service conception rate (FSCR) in Ovsynch treatment group in
summer and winter season was 25% and 27.8%, respectively. Moreover, in Doublesynch groups, FSCR was 40%
and 48% in summer and winter season, respectively. There were no any differences found in diameter of
preovulatory follicle (POF) following Ovsynch and Doublesynch treated groups. The overall mean diameter of
preovulatory follicle on the day of estrus was larger (p<0.05) in pregnant buffaloes as compared to non-pregnant
(14.6 ± 0.4 vs 12.7 ± 0.3 mm, respectively). Corpus luteum diameter on day 10 post-AI and estradiol concentration
on the day of AI were positively correlated (CL: r=0.72 and E2: r=0.84, p<0.05) with POF diameter. Retrospective
study showed that Doublesynch group’s buffaloes had higher ovulation rate after first GnRH injection as compared
to Ovsynch groups and hence had higher pregnancy rate as compared to Ovsynch in summer as well as in winter
season. In Ovsynch treatment groups, concentration of MDA was significantly higher (p<0.05) during summer
season as compared to its counterpart in winter season while GSH-Px and SOD were found similar (p>0.05).
Buffaloes of Doublesynch treatment groups showed significantly higher (p<0.05) MDA level in summer season as
compared to its counterpart in winter season on days 7, 9 and AI. However, GSH-Px and SOD levels were similar
between summer and winter season. The concentration of Zn was found significant lower (p<0.05) on days 0 and
AI in summer as compared to winter season in Ovsynch groups (1.0 ± 0.1 vs 1.5 ± 0.1 and 1.3 ± 0.1 vs 1.7 ± 0.1
ppm, respectively), while plasma Cu, Ca and P were lowers on the day of start of protocol in summer as compared
to winter season. Plasma Cu and Ca levels were observed similar on the day of start of protocol and day of AI
between summer and winter season while on the day of AI, Zn concentration was higher in summer buffaloes as
compared to winter ones . Phosphorus was higher in winter as compared to summer buffaloes. Ovsynch and
Doublesynch treated buffaloes in summer and winter season showed non significant variation in plasma
progesterone during days of treatment in respective protocol. In conclusion; Doublesynch protocol can be used as
estrus synchronization protocol in both seasons to achieve acceptable pregnancy rate.